Fabrication method of liquid crystal display device

ABSTRACT

A fabrication method of a liquid crystal display device uses a printing method which forms a pattern of a wider effective line width such as a gate line, a data line, a passivation layer, a pixel electrode, etc. constituting an LCD device. The inventive lithography process uses a mask that is applied at the time of forming a channel region having a narrow effective line width. Accordingly, the amount of resist used may be reduced, and the fabrication process can be simplified. This printing method can be used to fabricate a color filter substrate of an LCD device.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The invention relates to a fabrication method of a liquid crystaldisplay (LCD) device, and more particularly, to a fabrication method ofan LCD device including a printing method for a gate or date line usingpattern having a wider effective line width.

[0003] 2. Description of the Related Art

[0004] Generally, an LCD device includes a thin film transistor (TFT)array substrate having TFTs formed at each intersection of multiple gatelines and data lines, a color filter substrate facing the TFT arraysubstrate and having a color filter layer for displaying a color image,and a liquid crystal filled between the TFT array substrate and thecolor filter substrate.

[0005] The TFT array substrate has a plurality of gate lines arearranged in parallel, and a plurality of data lines are arranged in aperpendicular state to the gate lines. An intersection between the gatelines and the data lines defines a unit pixel region, and TFTsrespectively formed at the intersection regions function as switchingdevices. The TFTs form a matrix arrangement on the TFT array substrate.

[0006] The color filter substrate lies opposed to the TFT arraysubstrate and has a color filter layer constituted with sub color filterlayers of R (red), G (green), and B (blue) for displaying an image as acolor

[0007] A common electrode for applying an electric field to a liquidcrystal can be further provided at the color filter substrate so as tocorrespond with a pixel electrode formed on the TFT array substrate.

[0008] In order to apply an electric field to the liquid crystal, a datasignal must be applied not only to the common electrode but also to thepixel electrode formed on the TFT array substrate. Here, the TFT servesas a switching device of the data signal.

[0009] Generally, the TFT includes a gate electrode, a source electrode,a drain electrode, and a channel region between the source and drainelectrodes.

[0010] A fabrication method of a related art TFT can be explained withreference to FIGS. 1A to 1F.

[0011]FIGS. 1A to 1F show a TFT fabrication process using 5-maskprocess.

[0012]FIG. 1A shows a gate electrode material 11 that is formed on asubstrate 1. The gate electrode material of a metal can be formed on thesubstrate by a sputtering method. The metal layer forming the gate linecan constitute one electrode of a storage region for maintaining avoltage during the time of the TFT operation, and a gate pad pattern ata gate pad portion.

[0013]FIG. 1B shows that, after forming the gate metal layer, aphotoresist is deposited on the gate metal layer, and photolithographyusing a first mask M respectively forms a gate line, one electrode of astorage region, and a gate pad portion pattern 2 on the substrate 1.

[0014]FIG. 1C shows a gate insulating layer 3, a semiconductor layer andhigh concentrated N+ layer that are sequentially formed on the resultingmaterial. Then, photoresist is deposited and photolithography using asecond mask (not shown) selectively etches the semiconductor layer andthe high concentration N+ impurity layer to thus form an active layer 4above the channel region. Here, the active layer 4 is formed by stackingan amorphous silicon (a-Si) layer as a semiconductor layer and a highconcentration N+ layer.

[0015] The insulating layer 3 and the active layer 4 are usuallydeposited by a plasma enhanced chemical vapor deposition (PECVD) method.

[0016] Then, a conductive material is formed on the active layer, and asshown in FIG. 1D, a photolithography process is performed by using athird mask (not shown) to thus selectively etch so that the conductivematerial can be applied as source/drain electrodes 5 and 6 that areseparated from each other at the channel region. The conductive materialmay be applied as one electrode of a storage capacitor at the storageregion, and the conductive material may be applied as a data electrode 8at the data pad portion.

[0017]FIG. 1E shows a passivation layer 9 that is formed on theresulting material, and photolithography using a fourth mask (not shown)selectively etches so that the drain electrode of the channel region,the storage electrode 7 of the storage region, the gate pattern 2 of thegate pad portion, and the data electrode 8 of the data pad portion canbe exposed.

[0018]FIG. 1F shows a pixel electrode material that is formed on theresulting material. Then, photolithography process using a fifth mask(not shown) forms a pixel electrode 10 for connecting the drainelectrode 6 of the channel region and the storage electrode 7 of thestorage region, and a gate line 11 (connected to the gate pattern 2 ofthe gate pad portion) and a data line 12 (connected to the dataelectrode 8 of the data pad portion) are formed.

[0019] In this process, the five masks were consecutively applied toform the LCD device.

[0020] However, in the step for forming the gate electrode, the step forforming the active layer, the step for forming the source/drainelectrodes, the step for forming the contact hole in the passivationlayer, and the step for forming the pixel electrode, the process forforming each pattern involves depositing photoresist by a spin coaterand exposing. The spin coater uniformly deposits photoresist on asubstrate by dropping a predetermined amount of photoresist on thesubstrate where a metal layer is deposited, and by rotating thesubstrate at high speed. The spin coater method has a problem arisingfrom only partial utilization of the photoresist dropped on thesubstrate being used during the subsequent exposure process, and most ofthe photoresist is not used. Accordingly, a large amount of photoresistis uselessly discarded, and only a small amount of photoresist is usedduring the lithography process. Only approximately 10% of thephotoresist deposited by a single spin coating application is used inthe lithography process, and a small amount of the used photoresist,approximately 10-20%, is used during the actual pattern forming.

[0021] Also, an expensive mask is used to perform the photolithographyprocess.

SUMMARY OF THE INVENTION

[0022] Therefore, an object of the invention is to provide a fabricationmethod of an LCD device capable of reducing the fabrication cost andsimplifying processing. The inventive printing method is applied at thetime of forming a pattern of a wider effective line width such as a gateline, a data line, a pixel electrode, etc. constituting an LCD device. Alithography process using a mask is applied at the time of forming achannel region of a narrow effective line width.

[0023] The invention, in part, pertains to a fabrication method of aliquid crystal display device that includes forming a gate line on asubstrate by applying a gate photoresist pattern by printing,sequentially forming a gate insulating layer, a semiconductor layer, anda high-concentrated N+ layer over the gate line, forming an activeregion over the high-concentrated N+ layer by applying an activephotoresist pattern by printing, forming a conductive layer over theactive region, depositing a photoresist layer over the conductive layer,applying a mask over the photoresist layer, performing a lithographyprocess, and thereby forming a source/drain electrode, forming apassivation layer over the source/drain electrode, forming a contacthole over the passivation layer by applying a contact hole photoresistpattern by printing, and forming a pixel electrode on the passivationlayer by printing a pixel electrode photoresist pattern.

[0024] In the invention, the mask can include a channel region pattern.The printing is ink jet printing or roller printing. The step forforming the source/drain electrode can include defining an active layerby sequentially removing the high-concentrated N+ layer and thesemiconductor layer by using the active resist pattern formed byprinting as a mask, removing the active resist pattern, sequentiallyforming a conductive layer and a photoresist layer over the activelayer, exposing the photoresist layer, performing a development process,and thereby removing the photoresist layer above a channel region byusing the mask including the channel region pattern, and sequentiallyremoving the conductive layer and the high-concentrated N+ layer abovethe channel region.

[0025] The invention, in part, pertains to a fabrication method of aliquid crystal display device that includes forming a gate line over asubstrate by applying a gate resist pattern formed by printing,sequentially forming a gate insulating layer, a semiconductor layer, ahigh-concentrated N+ layer, and a conductive layer over the gate line,forming an active photoresist pattern over the conductive layer byprinting, exposing a part of the active photoresist pattern by applyinga mask over the active photoresist pattern, forming a source/drainelectrode by applying the partially exposed active photoresist patternas a mask, forming a passivation layer over the source/drain electrode,forming a contact hole over the passivation layer by applying a contacthole photoresist pattern formed by printing as a mask, and forming apixel electrode over the passivation layer by applying a pixel electrodephotoresist pattern formed by printing.

[0026] In the invention, the printing can be ink jet printing or rollerprinting. In the step for exposing a part of the active resist patternby applying a mask over the active photoresist pattern, an exposedregion can be a channel region and only a part of the active resistthickness can be exposed to a certain depth. The step for forming thesource/drain electrode can include removing the conductive layer, thehigh-concentration N layer, and the semiconductor layer by applying theactive photoresist pattern partially exposed by the mask as a mask,removing an exposed part of the active photoresist pattern and therebyexposing the conductive layer formed above the channel region, removingthe exposed conductive layer and the high-concentrated N+ layer, andremoving the active resist pattern.

[0027] The invention, in part, pertains to a fabrication method of aliquid crystal display device that includes forming a black matrix overa substrate, forming a color filter layer over the substrate byprinting, forming an overcoat layer over the color filter layer, forminga common electrode over the overcoat layer, and forming an alignmentlayer over the common electrode. The step for forming the color filterlayer can include forming a negative first photosensitive color resinover a substrate by printing, forming the first photosensitive colorresin only at a first sub color filter region by exposing and developingthe first photosensitive color resin by using a mask, printing a secondphotosensitive color resin over the substrate, and forming the secondphotosensitive color resin only at a second sub color filter region byexposing and developing the second photosensitive color resin by using amask, and printing a third photosensitive color resin on the substrate,and forming the third photosensitive color resin only at a third subcolor filter region by exposing and developing the third photosensitivecolor resin by using a mask.

[0028] The invention, in part, pertains to a liquid crystal displaydevice, that includes a substrate, a black matrix over the substrate, aprinted color filter layer over the substrate, an overcoat layer overthe color filter layer, a common electrode over the overcoat layer, andan alignment layer over the common electrode. The printed color filterlayer can include a printed first photosensitive color resin at a firstsub color filter region, a printed second photosensitive color resin ata second sub color filter region, and a printed third photosensitivecolor resin at a third sub color filter.

[0029] The foregoing and other objects, features, aspects and advantagesof the invention will become more apparent from the following detaileddescription of the invention when taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings, which are included to provide afurther understanding of the invention and are incorporated in andconstitute a part of this specification, illustrate embodiments of theinvention and together with the description serve to explain theprinciples of the invention.

[0031]FIGS. 1A to 1F are views showing a fabrication process of an LCDdevice in accordance with the related art.

[0032]FIG. 2 is a schematic construction view showing an injectionnozzle used at an ink jet printing method of the invention.

[0033]FIGS. 3A to 3J are views showing a fabrication process of an LCDdevice by a printing method according to the invention.

[0034]FIGS. 4A and 4B is a schematic explanatory view showing aprinciple of a roller printing method according to the invention.

[0035]FIGS. 5A to 5E are views showing a fabrication process of an LCDdevice by a printing method according to another embodiment of theinvention.

[0036]FIGS. 6A to 6E are views showing a fabrication process of a colorfilter substrate of an LCD device by a printing method according to theinvention.

DETAILED DESCRIPTION

[0037] Reference will now be made in detail to the preferred embodimentsof the invention, examples of which are illustrated in the accompanyingdrawings.

[0038] The inventive printing method forms a resist pattern by using anink jet injection by a thermal transfer method capable of forming apattern having a minute line width.

[0039]FIG. 2 shows a principle of the ink jet printing by a thermaltransfer method.

[0040] A thermal transfer injection nozzle and associated elementsinclude: a silicon substrate 201; a resist storing layer 202 for storingan injected resist; a thin film resistor 206 for heating athinly-deposited resist electrically; vapor 205 heated by the thin filmresistor 206 and injecting a resist; and an injection hole plate 203including an injection hole that injects a resist.

[0041] The thermal transfer injection nozzle is operated as follows.

[0042] When a resist stored in a resist storage device (not shown) isinjected into an injection nozzle mounted over a thin film resistor 206at lower surface thereof, the resist is heated by the thin film resistor206 to thereby generate vapor 205. The vapor 205 upon further heated bythe thin film resistor 206 expands, and thus bursts to be discharged ina stream 204 through an injection hole 207. The empty space caused bythe vapor burst is then filled with additional resist by the pressuredifference. This process is performed within a short time correspondingto several tens of microseconds. However, the time can vary, and timesas low as 1 microsecond and as high as 100 microseconds can be used.

[0043] A fabrication method of an LCD device using the inventive ink jetprinting method and the inventive injection nozzle will be explainedwith reference to FIGS. 3A to 3F.

[0044] First, a metal layer to be used as a gate electrode is depositedon a substrate 300, preferably by a sputtering method. The metal layerconstitutes not only a gate electrode, but also one electrode of astorage region and an electrode of a gate pad portion.

[0045] After depositing the metal layer, a gate electrode patterncomposed of a photoresist is formed on the metal layer by an ink jetinjection method. Next, as shown in FIG. 3A, a gate line pattern 301forms by etching a gate electrode pattern that has been applied as amask. FIG. 3A shows a plan view of the gate line pattern, and FIG. 3Bshows a sectional view of the gate line pattern.

[0046]FIG. 3C shows a gate insulating layer 302, an amorphous siliconlayer 303, and an N+ high-concentrated impurity layer 304 that aresequentially formed over the gate line 301.

[0047]FIG. 3D shows an overlying photoresist pattern 306 that is formedby ink jet injection to define an active region.

[0048] As shown in FIG. 3E, the N+ layer 304 and the amorphous siliconlayer 303 on the residual regions where the resist is not deposited areetched and removed by using the photoresist 306 as a mask. Then, thephotoresist 306 is removed. Next, a conductive layer 305 for forming asource/drain electrode is deposited on the resulting material,photoresist 311 is deposited, a mask is applied, an exposure isperformed, and a source/drain electrode pattern is thereby formed. As aresult, the photoresist pattern 311 for forming a source/drain electrodeis complete. This mask is the only mask used in the invention.

[0049] Next, as shown in FIG. 3F, the conductive layer that is notcovered by the photoresist pattern 311 formed by the mask process isremoved by wet-etching. After the wet-etching, the high-concentrated N+layer 303 over the channel layer is removed by a dry etching, therebyelectrically separating the source electrode 305 a from the drainelectrode 305 b.

[0050]FIG. 3F shows that the source electrode 305 a and the drainelectrode 305 b are formed, and the channel layer is opened.

[0051] When the source/drain electrodes 305 a, 305 b are formed, a dataline and a storage electrode pattern 307 may be formed simultaneously byusing the mask process.

[0052]FIG. 3G shows a plane view of the source/drain electrode pattern,the data line, and the storage electrode pattern 307 of a capacitorformed at the storage region.

[0053]FIG. 3H shows that after forming the source/drain electrode, apassivation layer 308 is deposited over the resulting material. Thepassivation layer 308 may be formed by using a silicon nitridelayer-based inorganic layer or an organic layer of BCB(benzocyclobutene) or acrylic resin.

[0054] After forming the passivation layer 308, a photoresist patternfor forming a contact hole is deposited on the passivation layer byusing ink jet injection.

[0055]FIG. 3I shows the passivation layer being etched by using thephotoresist pattern for forming a contact hole as a mask, therebyforming a contact hole so that the drain electrode 305 b can be exposed.Then, a transparent electrode 312 is deposited over the passivationlayer including the contact hole. The transparent electrode can beformed from indium tin oxide (ITO) or indium zinc oxide (IZO).

[0056] After forming the transparent electrode over the entiresubstrate, a pixel electrode pattern resist 310 is deposited thereonusing ink jet injection.

[0057] Then, transparent electrode layer 312 is etched while using thepixel electrode pattern photoresist 310 as a mask, thereby forming apixel electrode 312 a.

[0058] The pixel electrode 312 a is a transparent conductive electrode,and is composed of indium tin oxide (ITO) or indium zinc oxide (IZO).

[0059] The explanation above covered a fabrication method of an LCDdevice using ink jet injection method.

[0060] Hereinafter, a fabrication method of an LCD device using a rollerprinting method will be explained with reference to FIGS. 4A to 5E.

[0061] The fabrication method of an LCD device by a roller printingmethod is similar as the fabrication method of an LCD device by the inkjet injection method, except for the transfer method of the photoresist.

[0062]FIGS. 4A and 4B show a schematic explanation illustrating how apattern is transferred by roller printing.

[0063] In FIG. 4A, a cliché 401 has an intaglio pattern of a grooveform. A predetermined amount of photoresist 404 is deposited on thecliché 401. The deposited photoresist is contained in the groove. Extraphotoresist on the cliché 402 is removed by a photoresist removing meanssuch as a doctor blade (not shown) or a wire. Accordingly, the resist iscontained only in the intaglio pattern of the cliché 402.

[0064]FIG. 4A also shows a roller 403 in contact with the cliché inwhich the photoresist is contained. The roller 403 rotates on the cliche402 to thereby transfer the photoresist 404 contained in the cliche ontoa surface of the roller 403. As the result, the certain amount of resisttransfers onto the surface of the roller.

[0065] Next, the roller 403 is contacted with the substrate 401 androtated on the substrate 401, thereby re-transferring the resist patternonto the substrate 401.

[0066] Since the size of the roller 403 is smaller than that of thesubstrate, the processes are repeated several times, and the resistpattern thereby forms on the entire substrate. In the process forrepeating the re-transferring several times, inconsistency between eachpattern may be generated at the time of aligning patterns. Thismis-alignment may be solved by arranging a plurality of alignment markson the substrate and correctly positioning each pattern to eachalignment mark at the time of transferring.

[0067] The fabrication method of an LCD device by the roller printingmethod of the invention is the same as the fabrication method of an LCDdevice by the ink jet injection method shown in FIGS. 3A to 3J exceptthe following. In the method by the roller printing method, a rollerprinting method is used instead of an ink jet injection method as atransferring method of a resist.

[0068] That is, a pattern is formed by the roller printing method in astep for transferring a resist of a gate pattern onto a substrate, astep for transferring a resist of an active layer pattern onto asubstrate, a step for transferring a resist of a contact hole patternonto a passivation layer, and a step for transferring a resist of apixel electrode pattern onto the passivation layer.

[0069] The resist pattern formed at each step is applied as a mask of anetching process thus to form a corresponding layer such as a gate line,an active layer, and etc.

[0070] Preferred Embodiment 2

[0071] In the first preferred embodiment, the LCD device was fabricatedby lithography using four-time resist pattern transferring processes andone mask.

[0072] Hereinafter, more simplified fabrication method of an LCD deviceby a printing method will be explained. That is, the fabrication processof the LCD device is simplified by consecutively depositing a conductivelayer on an active layer and applying a partial exposure.

[0073] The fabrication method of an LCD device according to a secondembodiment of the invention includes forming a gate line on a substrateby applying a gate line pattern formed by a printing method,sequentially depositing a gate insulating layer, an active layer, and aconductive layer thereon, forming a resist pattern for defining anactive region by a printing method, exposing the resist pattern fordefining a channel region by using a mask, removing the conductive layerand the active layer existing at regions where the resist pattern is notformed, ashing the resist pattern, partially removing the conductivelayer above the channel region, and thereby forming a source/drainelectrode, forming a passivation layer on the source/drain electrode,forming a resist of a contact hole pattern by a printing method, andforming a transparent electrode on the passivation layer and forming apixel electrode by applying a pixel electrode pattern formed by aprinting method.

[0074] Details will be explained with reference to FIG. 5.

[0075]FIG. 5A shows a gate line 501 being formed on a substrate 500.Here, a resist of a gate pattern is deposited by a printing method. Thisprinting method can be either an ink jet printing method or a rollerprinting.

[0076] Next, a gate insulating layer 502, an amorphous silicon layer503, an N+ ohmic contact layer 504 formed by doping a high-concentrationimpurity, and a conductive layer 505 are sequentially formed on thesubstrate 500 where the gate line 501 is formed.

[0077] Then, a photoresist 506 for defining an active region of a TFT isformed by a printing method.

[0078]FIG. 5B shows an exposure being performed by using a mask M. Here,exposure energy is controlled in order to expose only a part of thephotoresist above the channel region. After development, the resistpattern 506 is stepped.

[0079] In a fabrication method of an LCD device using a conventionaldiffraction mask, photoresist is deposited using a spin coater, and anactive region and a source/drain electrode are formed by an expensivediffraction mask. However, in the preferred embodiment of the invention,a resist pattern for forming an active region is formed by a printingmethod, and a general mask capable of controlling an optical amount isused instead of the diffraction mask. Also, a stepped resist pattern isformed by controlling exposure energy. That is, the invention applies afeature that a degree of resist removed becomes different at the time ofdevelopment according to the degree of exposure to light.

[0080] Next, by using the stepped photoresist 506 as a mask, theconductive layer 505, the N+ ohmic contact layer 504, and the amorphoussilicon layer 503 are sequentially etched to thus be removed.

[0081]FIG. 5C shows a part of the stepped resist pattern 506 being ashedto thereby remove the resist above the channel region.

[0082] Then, the resist pattern separated by the ashing process is usedas a mask, and an etching process is performed to thereby etch theconductive layer and the N+ ohmic layer above the channel region.

[0083] As a result, a source electrode 505 a and a drain electrode 505 belectrically separated from each other are formed.

[0084]FIG. 5D shows that the source electrode 505 a and the drainelectrode 505 b are separated from each other.

[0085] A step of deposing a passivation layer 507 over the resultingstructure, a step of forming a contact hole over the passivation layer507, and a step of forming a pixel electrode 508 over the passivationlayer are performed using the same process as described above.

[0086]FIG. 5E shows that the passivation layer 507 and the pixelelectrode 508 are formed to complete a thin film transistor.

[0087] Preferred Embodiment 3

[0088] The fabrication method of an LCD device by a printing methodaccording to the invention may be applied not only to a fabricationmethod of a TFT array substrate including a TFT, but also to afabrication method of an upper color filter substrate of an LCD device.

[0089] The fabrication of a color filter substrate of an LCD device by aprinting method according to the invention includes forming a blackmatrix on a substrate, depositing photosensitive color resin on theblack matrix by a printing method, forming a color filter layer by anexposure, forming an overcoat layer so as to compensate a step of thecolor filter layer; forming a common electrode, and forming an alignmentlayer on the common electrode.

[0090] The fabrication method of a color filter substrate using aprinting method according to the invention will be explained withreference to FIGS. 6A to 6E.

[0091]FIG. 6A shows a substrate 601 for fabricating a color filtersubstrate. A black matrix 602 is formed over the transparent substrate601.

[0092] A black matrix is generally formed between sub color filterlayers of R (red), G (green), and B (blue). The black matrix shieldslight passing through a reverse tilt domain formed at the peripheryportion of a pixel electrode of a lower TFT array substrate. Thematerial of the black matrix may a metal thin film such as Cr, or anorganic carbon material such as organic pigments can be used. The blackmatrix can be a pigment-dispersed type or a photopolymerization type.

[0093]FIG. 6B shows a color filter layer using color resin of R, G, andB. As the color resin, a photosensitive color resin such as a monomer, abinder, etc. is used.

[0094] In the invention, it is advantageous to use a negative-typephotosensitive color resin, which remains without being removed duringthe development process at the time of irradiating light energy.However, a positive-type photosensitive color resin can be also used.

[0095] Next, a color filter layer is formed over the substrate 601 wherethe black matrix 602 is formed. The color filter layer may constitutesub color filter layers of R, G, and B. A process for forming the subcolor filter layers with R, G, and B sublayers according to a preferredembodiment of the invention will be explained.

[0096]FIG. 6B shows a red color resin that is transferred onto a regionwhere a red sub color filter layer is to be formed by printing. Then,the red color resin is exposed by using a mask having the shape of thesub color filter layer pattern. Since the red color resin is a negativephotosensitive resin, the color resin of a light-irradiated regionremains during the develop process, and the color resin which has beenunexposed to light is removed in the developing process. As a result,the sub color filter layers may be precisely formed at the color filterregion.

[0097]FIG. 6C shows the same process being performed for a green colorresin 603 b. That is, a green color resin is transferred onto thesubstrate by a printing method. Then, an exposure process is performedby using a mask, and the color resin which has not been exposed isremoved during development.

[0098] The mask used for the red colored resin can be also used for thegreen colored resin, because the size of every sub color filter layer isthe same.

[0099]FIG. 6D shows the process being repeated for a blue color filterlayer using a blue colored resin.

[0100] Over the substrate where the color resin has been deposited bythe printing method, as shown FIG. 6E, an overcoat layer 604 forcompensating a step of the color resin, and a common electrode 605 forapplying an electric field to a liquid crystal and an alignment layer607 are sequentially formed. Afterwards, the common electrode 605, aspacer 606 for spacing a TFT array substrate and a color filtersubstrate may be further formed.

[0101]FIG. 6E shows the completed color filter substrate.

[0102] In the invention, a printing method, having less minuteness buteasy processing, is applied at the time of forming a pattern of a widereffective line width. A lithography process using a mask is applied atthe time of forming a minute part such as the channel region with anarrow effective line width. Accordingly, processes are simplified, anda large amount of photoresist or color resin is not uselessly discarded.

[0103] Also, the resist pattern of each layer is formed by the printingmethod of the invention, and not only the photosensitive resist but alsovarious kinds of resins may be used. The reason is because the resistused in the invention does not require an exposure process for forming acertain pattern and has only to be used as an etching mask at thelithography process. Many types of photoresists can be used in theprocess, including positive, negative, e-beam and UV resists.

[0104] As the invention may be embodied in several forms withoutdeparting from the spirit or essential characteristics thereof, itshould also be understood that the above-described embodiments are notlimited by any of the details of the foregoing description, unlessotherwise specified, but rather should be construed broadly within itsspirit and scope as defined in the appended claims, and therefore allchanges and modifications that fall within the metes and bounds of theclaims, or equivalence of such metes and bounds are therefore intendedto be embraced by the appended claims.

What is claimed is:
 1. A fabrication method of a liquid crystal displaydevice, comprising: forming a gate line on a substrate by applying agate photoresist pattern by printing; sequentially forming a gateinsulating layer, a semiconductor layer, and a high-concentrated N+layer over the gate line; forming an active region over thehigh-concentrated N+ layer by applying an active photoresist pattern byprinting; forming a conductive layer over the active region; depositinga photoresist layer over the conductive layer; applying a mask over thephotoresist layer, performing a lithography process, and thereby forminga source/drain electrode; forming a passivation layer over thesource/drain electrode; forming a contact hole over the passivationlayer by applying a contact hole photoresist pattern by printing; andforming a pixel electrode on the passivation layer by printing a pixelelectrode photoresist pattern.
 2. The method of claim 1, wherein themask includes a channel region pattern.
 3. The method of claim 1,wherein the printing is ink jet printing or roller printing.
 4. Themethod of claim 1, wherein the step for forming the source/drainelectrode comprises: defining an active layer by sequentially removingthe high-concentrated N+ layer and the semiconductor layer by using theactive resist pattern formed by printing as a mask; removing the activeresist pattern; sequentially forming a conductive layer and aphotoresist layer over the active layer; exposing the photoresist layer,performing a development process, and thereby removing the photoresistlayer above a channel region by using the mask including the channelregion pattern; and sequentially removing the conductive layer and thehigh-concentrated N+ layer above the channel region.
 5. A fabricationmethod of a liquid crystal display device, comprising: forming a gateline over a substrate by applying a gate resist pattern formed byprinting; sequentially forming a gate insulating layer, a semiconductorlayer, a high-concentrated N+ layer, and a conductive layer over thegate line; forming an active photoresist pattern over the conductivelayer by printing; exposing a part of the active photoresist pattern byapplying a mask over the active photoresist pattern; forming asource/drain electrode by applying the partially exposed activephotoresist pattern as a mask; forming a passivation layer over thesource/drain electrode; forming a contact hole over the passivationlayer by applying a contact hole photoresist pattern formed by printingas a mask; and forming a pixel electrode over the passivation layer byapplying a pixel electrode photoresist pattern formed by printing. 6.The method of claim 5, wherein the printing is ink jet printing orroller printing.
 7. The method of claim 5, wherein in the step forexposing a part of the active resist pattern by applying a mask over theactive photoresist pattern, an exposed region is a channel region andonly a part of the active resist thickness is exposed to a certaindepth.
 8. The method of claim 5, wherein the step for forming thesource/drain electrode comprises: removing the conductive layer, thehigh-concentrated N layer, and the semiconductor layer by applying theactive photoresist pattern partially exposed by the mask as a mask;removing an exposed part of the active photoresist pattern and therebyexposing the conductive layer formed above the channel region; removingthe exposed conductive layer and the high-concentrated N+ layer; andremoving the active resist pattern.
 9. A fabrication method of a liquidcrystal display device comprising: forming a black matrix over asubstrate; forming a color filter layer over the substrate by printing;forming an overcoat layer over the color filter layer; forming a commonelectrode over the overcoat layer; and forming an alignment layer overthe common electrode.
 10. The method of claim 9, wherein the step forforming the color filter layer comprises: forming a negative firstphotosensitive color resin over a substrate by printing; forming thefirst photosensitive color resin only at a first sub color filter regionby exposing and developing the first photosensitive color resin by usinga mask; printing a second photosensitive color resin over the substrate,and forming the second photosensitive color resin only at a second subcolor filter region by exposing and developing the second photosensitivecolor resin by using a mask; and printing a third photosensitive colorresin on the substrate, and forming the third photosensitive color resinonly at a third sub color filter region by exposing and developing thethird photosensitive color resin by using a mask.
 11. The method ofclaim 9, wherein the printing is ink jet printing or roller printing.12. A liquid crystal display device, comprising: a substrate; a blackmatrix over the substrate; a printed color filter layer over thesubstrate; an overcoat layer over the color filter layer; a commonelectrode over the overcoat layer; and an alignment layer over thecommon electrode.
 13. The liquid crystal display device of claim 12,wherein the printed color filter layer comprises: a printed firstphotosensitive color resin at a first sub color filter region; a printedsecond photosensitive color resin at a second sub color filter region;and a printed third photosensitive color resin at a third sub colorfilter.
 14. The liquid crystal display device of claim 12, wherein theprinted color filter layer has been ink jet printed or roll printed.